Delayed Heterologous SARS-CoV-2 Vaccine Dosing (Boost) After Receipt of EUA Vaccines

The primary objectives of this study are to evaluate the safety and reactogenicity of delayed heterologous or homologous vaccine doses after Emergency Use Authorization (EUA)-dosed vaccines and to evaluate the breadth of the humoral immune responses of heterologous and homologous delayed boost regimens following EUA dosing.

What does the study involve?

All trial participants will be followed for one year after receiving their last vaccination as part of the study. They will be asked to complete telephone check-ins and various in-person follow up visits. Trial investigators will evaluate participants for safety and any side effects post-vaccination. Participants also will be asked to provide blood samples periodically so that trial investigators can evaluate immune responses against current circulating strains of SARS-CoV-2, as well as emerging variants. If trial participants develop laboratory-confirmed symptomatic COVID-19, investigators will perform genetic sequence analyses on the participant samples to see if a variant strain of SARS-CoV-2 caused the infection.

Who can participate?

Individuals 18 years of age and older, who are in good health, have no known history of COVID-19 or SARS-CoV-2 infection, and meet all other eligibility criteria. 

Where is it taking place?

This study will be conducted at several sites throughout the United States. Visit search query NCT04889209 for a list of locations.

Participating in Research

Watch a series of short informational videos about participating in clinical trials. These videos are intended to help potential participants understand how research works, what questions they should consider asking, and things to think about when deciding whether or not to participate in a study.

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